Drill string element handling apparatus

ABSTRACT

An arrangement for the handling of drill string elements, such as tubes or rods, in drill rigs, comprising means for transferring the drill string elements between a magazine and the drill string axis, a drill string centralizer at the front end of an elongated support for guiding the drill string, a spinning device on said transferring means for gripping and rotating a drill string element, said means being adapted to axially displace the drill string element during rotation thereof, and a sleeve brake mounted on the drilling machine for nonrotatably holding a coupling sleeve when the adapter of the drilling machine is disconnected from the drill string.

This invention relates to an arrangement for transferring drill rods ordrill pipes to and fro between a magazine and a drill string made up bythese rods or pipes and for connecting and disconnecting the rods orpipes, comprising a spinning device for gripping and rotating the drillrod. The spinning device is movably mounted for transferring the drillrod along a path between the magazine and the drill string axis at themovement thereof.

Rock drilling rigs with arrangements for automatic handling drill pipesare previously known. In one known rig, by way of example, the drillpipes are placed in an arcuate magazine and are transferred to the drillaxis by means of a swingable gripping arm. In another known drill rigthe pipe rack itself is movably mounted on the framing. In both of thesepreviously known constructions the rotary drive unit of the drillingmachine is used for the assembling and disassembling of the drill pipes.Such constructions are disclosed for instance in U.S. Pat. No. 3,506,075and U.S. Pat. No. 2,972,388. In still another drill rig, disclosed inU.S. Pat. No. 3,177,944, the drill pipes are placed in a horizontalmagazine and are movable to a vertical position parallel with the drillaxis by means of two gripping arms. A swingable arm with a grippingmeans designed as three rollers resting against the pipes is arranged totransfer the pipes to the drill axis. The gripping arm is placed on amounting which can be raised and lowered by mans of an hydrauliccylinder for attaining the axial displacement between two drill pipeswhich is necessary during assembling and disassembling.

An object of the present invention is to provide an arrangement forhandling drill rods or drill pipes in a simplified, cheaper and morerapid manner when compared with known arrangements, whereby the deadtime in connection with the drilling can be substantially reduced.

The above and other purposes of the invention will become obvious fromthe following description and from the accompanying drawings in whichone embodiment of the invention is shown by way of example. It should beunderstood that this embodiment is only illustrative of the inventionand that various modifications thereof may be made within the scope ofthe claims following hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows diagrammatically a side view of a crawler mounted rockdrilling rig with a rod handling system according to the invention;

FIG. 2 shows a section through a magazine for drill rods, taken alongthe line II--II in FIG. 1;

FIG. 3 shows a section through a turnstile separating two consecutiverods in the magazine, taken along the line III--III in FIG. 2;

FIG. 4 shows the magazine bottom, taken along the line IV--IV in FIG. 1;

FIG. 5 shows a section through the magazine bottom, taken along the lineV--V in FIG. 4;

FIG. 6 is a longitudinal section showing a swingable transferring armwith rod-gripping tongs;

FIG. 7 shows a fragmentary section through the gripping tongs, takenalong the line VII--VII in FIG. 6;

FIG. 8 shows a top view of the transferring arm and the magazine, takenalong the line VIII--VIII in FIG. 1;

FIG. 9 is a bottom view of the transferring arm system in FIG. 6 showinghow the gripping tongs are arranged to be turned at the swinging of thetransferring arm;

FIG. 10 shows a top view of a drill steel centralizer;

FIG. 11 shows a longitudinal section through the drill steelcentralizer, taken along the line XI--XI in FIG. 10;

FIG. 12 shows a top view of drill bit changing devices arranged at bothsides of the feed bar;

FIG. 13 is a longitudinal section through a drill bit changing device,taken along the line XIII--XIII in FIG. 12;

FIG. 14 shows a side view of a coupling sleeve brake arranged at thefront end of the rock drilling machine;

FIG. 15 shows a top view of the sleeve brake;

FIG. 16 shows a side view of a stop lug for the drill steel centralizer;

FIG. 17 shows a section through the stop lug, taken along the lineXVII--XVII in FIG. 16;

FIGS. 18 and 19 show diagrammatically respectively the hydraulic and theelectric control circuit for the transferring arm and the grippingtongs; and

FIG. 20 shows a pair of drill rods with a coupling sleeve therebetween.

DETAILED DESCRIPTION

In FIG. 1, a drill rig is diagrammatically shown, having a chassis 10,crawlers 11, an operator's cab 12, a machinery housing 13 accommodatinga Diesel engine, hydraulic pumps and a .[.compressor.]. .Iadd.compressor.Iaddend.unit, and a feed bar 14. A rock drilling machine 15, preferablyhydraulic, is in known manner movable along the feed bar 14. Duringdrilling, the chassis 10 is raised from the ground 17 by means ofhydraulic levelling jacks 16. A magazine for drill rods (also calledextension rods) 25 comprising three axially spaced members 22, 23 and 24is mounted beside the feed bar 14. The drill rods (i.e., extension rods)25, are moved one by one between the magazine and the drill axis bymeans of a swingable transferring arm 26 with a spinning device 27mounted on the outer end thereof. At the front end of the feed bar 14there is a drill rod centralizer 20 for a string 18 of coupled extensionrods. The drill rod centralizer 20 is mounted on a slide which is freelyslidable along the feed bar. In FIG. 1, the drill rod centralizer isshown in a rear position where it can be locked by means ofhydraulically operated lugs 290. At either side of the feed bar there isa drill bit changing device 21 swingably journalled in such a way thatit can be swung to the drill axis, when the drill rod centralizer 20 isin the shown position and the drill bit 19 is drawn up thereinto. Thedrill rods (or extension rods) 25 have threaded ends, as isconventional, for threaded engagement with a coupling sleeve 221 (FIG.20) to connect drill rods end-to-end to form a drill string 18.

As may be seen in FIG. 2 the magazine member 23 attached to the feed bar14 is provided with an arcuate channel 28. A bar 31 is placed outsidethe bottom of the channel on the extension of said circle arc extendingbetween the upper member 24 of the magazine and the bottom 22. Themagazine is stiffened by .[.eans.]. .Iadd.means .Iaddend.of verticalflanges 32, 33 and 34. On both sides of the channel 28 turnstiles 29 arerotatably journalled. Each turnstile is provided with four pins or wings30 each of which separates two consecutive rods. The turnstiles 29 arejournalled alternately on the one side and on the other of the channelfrom the opening to the bottom thereof. The turnstiles 29 are rotated bythe rods 25 during the transferring of the rods into or out of themagazine.

As evident from the section through a turnstile 29 shown in FIG. 3, thelatter is journalled between two parallel plates 38 and 39. Theturnstille 29 is attached to a shaft 41 by means of a wedge 40. A tube44 is affixed to the plate 39. Between a collar 43 on the shaft 41 and alock ring 45 fastened in the tube 44 there is provided a spring 42. Atboth sides of the spring between the latter and respectively the collar43 and the lock ring 45 there are slide rings 48 and 49 respectively. Aplate 50 providing a bearing bushing is attached to the plate 38 bymeans of bolts 52. The end of the plate 50 which faces the turnstile 29is provided with a waved cam profile 51. The wedge 40 extends before theturnstile 29 and is biased against the cam profile 51 by the spring 42.The cam profile 51 is provided with four tops and four bottoms. When theturnstiles 29 are in the position shown in FIGS. 2 and 3 the wedge 40rests against a bottom in the cam profile 51. If a rod 25 is moved intoor out of the magazine, the rod will turn the turnstile 29 by thecontact with a pin 30. The wedge 40, then, will slide along the camprofile 51 and contract the spring 42. The turnstile 29 is turned by therod until the wedge 40 passes a top on the cam profile 51. The continuedturning of the turnstile until the wedge reaches the bottom immediatelyfollowing in the cam profile is carried out by extension of thecontracted spring 42. The spring force is so chosen that it is greatenough to prevent the rods from falling unintentionally out of themagazine, for instance when the feed bar 14 is inclined. The uppermember 24 of the magazine is designed in the same way as the member 23.

In FIGS. 4 and 5, the bottom member 22 of the magazine is shown. Thebottom member, which in conformity with the members 23 ad 24 of themagazine is attached to the feed bar 14, is stiffened by means offlanges 36 and 37. The rods are stored in an up-right position standingagainst the plane bottom surface in an arcuate channel 35 designed withan U-shaped cross section.

In FIG. 6, the longitudinal section through the transferring arm 26 withthe spinning device 27 shows that the transferring arm comprises twoarms 56 and 57 perpendicular to the feed bar 14, which arms are mutuallyconnected by a bar 58. A trunnion 61 provided with internal splines isattached to the arm 56. A pivot 60 of an hydraulic motor 59 is stuckinto the trunnion 61, which pivot is provided with splines. The motor 59is mounted on a bracket 62 which is fastened with screws to the feed bar14. A pivot 64 is attached to the arm 57. The pivot 64 is journalled ina bearing 65 which is mounted in a bracket 63, which bracket is fastenedwith screws to the feed bar 14. The spinning device 27 .[.comprise.]..Iadd.comprises .Iaddend.two rectangular plates 66 and 67 which areconnected to each other by side pieces 68 and 69. A trunnion 87 providedwith internal splines is attached to the plate 66. A pivot 71 of anhydraulic motor 72 is stuck into the trunnion, which pivot is providedwith splines. The motor 72 is mounted on the arm 56. A pivot 70 isattached to the lower plate 67. This pivot is journalled in a bearing 73which is mounted in a journal casing on the arm 57. Two rollers 76 and77 are swingably attached to the plate 67.

As may be seen in FIG. 7 the rollers 76 and 77 respectively arejournalled on the outer end of arms respectively 101 and 102. These armsare swingable around shafts 103 and 104, which are mounted on the plate67. The arms 101 and 102 are swung by means of a double acting hydrauliccylinder 79, the movement of which is transferred to the arms 101 and102 respectively via link arms respectively 105 and 106.

A mounting plate 81 extends between the side pieces 68 and 69, whichmounting plate carries a reversible hydraulic motor 83. A roller 85 isattached to the pivot of the motor 83. The axes of the rollers 76, 77and 85 are inclined in relation to the drill axis, whereby the anglebetween each of the axes of the rollers and the drill axis is equal tothe pitch angle of the thread of the extension rod. Rollers 74 and 75are swingably mounted on the plate 66 by means of an hydraulic cylinder78. An hydraulic motor 82 is mounted on a mounting plate 80 extendingbetween the side pieces 68 and 69. The motor 82 drives reversibly aroller 84. The rollers 74, 75 84 and 76, 77, 85 respectively formaxially spaced gripping tongs for a drill rod.

In FIG. 8, the path L is shown along which a drill rod 25 moves betweenthe magazine and the drill axis. The arm 56 with the rollers 74, 75 and84 gripping a drill rod 25, is swung by means of the motor 59 until theaxis of the motor 72 reaches the point 0. The motor 59, then, is stoppedand the motor 72 starts turning the frame 66, 67, 68 and 69, whereby therod 25 moves along a circular arc to the side of the arm 56 which facesthe magazine member 23. The motor 72 is stopped and, at the same time,the motor 59 continues swinging the arm 56, whereby the rod 25 is movedinto the channel 28. The rod 25 is moved as far as possible into thechannel 28, in FIG. 8 shown with chain-dotted lines, where a continuedmovement is prevented by the rod being in the magazine and by the pins30 of the turnstiles 29 positioned between the rods. Adjustable setscrews, not shown, for adjusting the moving path L of the drill rod areprovided on the arm 56 on the one hand at the swinging centre of the armand on the other at the outer end thereof, these set screws beingintended to cooperate with stop means mounted on the feed bar and on theplate 66 respectively for determining respectively the end position ofthe swinging of the .[.aam.]. .Iadd.arm .Iaddend.56 and the end positionof the turning of the gripping tongs.

In FIG. 9, the control means are shown for the turning of the spinningdevice 27 on the transferring arm 26. On the underneath side of the arm57 a resiliently swingable arm 107 .Iadd.is .Iaddend.journalled in sucha way that it strives to return to an .[.intial.]. .Iadd.initial.Iaddend.position upon being swung. The arm 107 carries a metal plate112, which will cover a sensor 113 with a mutual spacing at the swingingof the arm. The sensor, which emits a signal at the covering, isattached to the journal casing 86 on the bracket 63. The outer end ofthe pivot 70 carries a round plate 109. Two pins 110 and 111 areattached to the plate. If the arm 57 is swung in the direction of thearrow A the plate 112 will partly cover the sensor 113. In this positionthe pivot of the motor 72 has reached the point 0 in FIG. 8. The motor59 is stopped by a signal emitted from the sensor 113, which signalbesides is used to start the motor 72. The latter rotates the plate 109in the direction of the arrow B until the pin 111 abuts the arm 107. Thearm 107, then is swung in the counter clockwise direction by means ofwhich the mutual covering of the sensor members 112 and 113 ceases. Thesignal emitted from the sensor starts the motor 59, whereby thetransferring arm continues to swing. When the arm 57 is swung in theopposite direction, the pin 110 will control the sensor in analogousmanner. In FIGS. 18 and 19, the hydraulic and the electric controlcircuit respectively for the transferring arm 26 and the spinning device27 are shown diagramatically. A contact breaker 89 and a contact breaker90 can be actuated individually by means of a manipulator 88. If a drillrod is to be transferred from the magazine to the drill axis the contactbreaker 89 is actuated. An electromagnet 98, then, will adjust the valve93 in such a way that pressure fluid from the pump 100 is conducted tothe motor 59, whereby the swinging of the arm 57 starts. When the plate112 has reached the sensor 113 a signal is emitted therefrom, whichsignal actuates a relay 99. The latter cuts the tension to the magnet98, whereby the valve 93 is readjusted and the motor 59 stops. At thesame time the relay 99 closes the circuit through the magnet 94, wherebythe valve 91 is adjusted. Since the magnet 96 has adjusted the valve 92pressure fluid will be conducted to the motor 72, by which the latterstarts to turn the gripping tongs in a clock-wise direction according tothe arrow B in FIG. 9. The gripping tongs are turned until they abutmechanical stopping means, not shown. When the plate 112 is moved awayfrom the sensor 113 by the pin 111, the magnet 98 once again is putunder tension, by means of which the valve 93 again is adjusted and themotor 59 continues to swing the arm 57 until the drill rod reaches thedrill axis.

When a drill rod is to be transferred from the drill axis to themagazine, the contact breaker 90 is actuated. The magnet 97, then, willadjust the valve 93 in the opposite direction, by means of which themotor 59 starts to swing the arm 57 towards the magazine. When the plate112 has reached the sensor 113 the relay 99 is actuated once again,whereby the magnet 97 becomes dead and the motor 59 stops. At the sametime the magnet 95 is put under tension, by means of which the valve 91is adjusted in such a way that the motor 72 starts to turn the grippingtongs in the counter clockwise direction, FIG. 9. The gripping tongs areturned until they abut mechanical stopping means, not shown. When thegripping tongs have been turned so much that the plate 112 is moved awayfrom the sensor 113 by the pin 110, time the magnet 97 is put undertension, by means of which the valve 93 once again is adjusted and themotor 59 continues to swing the arm 57 until the drill rod has reachedthe magazine.

In the embodiment shown as an example the extension rods are coupled byusing detachable coupling sleeves. At disassembling it is thereforenecessary to make sure that the right thread connection in the sleeve isloosened. A sleeve brake 151 is therefore mounted on the front end ofthe rock drilling machine 15. The sleeve brake (FIGS. 14 and 15)comprises two fork legs 152, 153 which rest against diametricallyopposed sides of a sleeve 221 at the braking thereof. Besides hexagonalsleeves, shown in FIG. 15, also round sleeves can be used. The fork legs152, 153 are swingable around shafts 154, 155 mounted on the outer endof an arm 161. The arm 161 is swingable around a shaft 162 in a bracket165 by means of a cylinder 164. The bracket 165 is supported by twoshafts 166, 167 mounted on a plate 163 which is attached to the frontend of the rock drilling machine 15. The shafts 166, 167 are preferablysurrounded by resilient bushings so that the impulse waves from theimpactor of the rock drilling machine 15 are not to be transmitted tothe sleeve brake 151. A shaft 158 extends transversally through the forklegs 152, 153. The fork legs can be moved away from each other againstthe action of springs 156, 157 mounted on the shaft 158. The springs arelocked by nuts 159, 160. At drilling, the sleeve brake 151 is in theposition shown with continuous lines in FIG. 14. When the adapter of therock drilling machine is to be unscrewed out of a coupling sleeve, thedirection of rotation of the rock drilling machine is reversed. During areversed rotation of the rock drilling machine the sleeve brake 151 isswung automatically to the position shown with chain-dotted lines inFIG. 14 by means of the cylinder 164 .Iadd.actuated by the supply pump100 and reverse rotation sensing means 300. .Iaddend.The fork legs 152,153, then, wil lock the sleeve against rotation, by which is safeguardedthat the sleeve remains on the drill rod.

As evident from the longitudinal section through the drill rodcentralizer 20 shown in FIG. 11 the latter consists of substantially twomembers, a tubular member 201 and a prism shaped member 202. A flange203 is welded to the upper part of the tube 201. The flange 203 isconnected to the member 202 by means of screws 204. The drill rodcentralizer is mounted on a slide 205, which is slidable along the feedbar 14. A plate 206 is welded to the upper part of the slide. The member202 is attached to the plate 206 by means of screws 207. The tubularmember 201 is attached to the lower part of the slide 205 by means of aclamp 208. A flange 225 is attached to the lower most portion of thetube 201. Two co-operating hydraulically controlled jaws 209 and 210 areslidably mounted in the prism shaped member 202. The jaw 209 is movable(FIG. 10) by means of an arm 212, a second arm 213 pivotally connectedto said arm, which second arm is swingable about a shaft 214 and bymeans of a piston rod 215 of a cylinder, which piston rod is pivotallyconnected to the opposite end of the arm 213. In a position wherebrought together the jaws 209 and 210 provide between themselves a firstcylindrical part 216, the diameter of which is a little larger than thatof the drill rod. A second cylindrical part 217 has a diameter which isa little smaller then the outer diameter of a coupling sleeve 221 whichconnects two drills rods to each other. A plate 219 is fastened to theupper side of the member 202 by means of screws 220. A cylindricalsleeve 218 is welded to the plate 219. The sleeve 218 has substantiallythe same inner diameter as the outer diameter of the coupling sleeve221. A seal ring 222, preferably of a plastic material, is inserted atthe upper part of the tube 201 between said part and the member 202. Asecond tube 223 is welded to the envelope surface of the tube 201 atabout the middle thereof. Inside the tube 201 between the upper partthereof and the tube 223, there is a sleeve 224 firmly attached to thetube 201. The inner diameter of the sleeve 224 accords substantiallywith the outer diameter of the coupling sleeve 221. The tube 201 isintended to guide the drill bit at the collaring of a new hole, forwhich reason the inner diameter of the tube substantially accords withthe outer diameter of the drill bit.

On either side of the feed bar 14 (FIG. 16), there is a stop lug 290 forthe slide 205 of the drill rod centralizer. The stop lug 290 is guidedbetween two parallel plates 291, 292 fastened with screws to each other.The plate 292 is attached to the feed bar 14. The piston rod of acylinder 293 is pivotally connected to the plate 291 by means of a shaft294. The rear part 295 of the cylinder is pivotally connected to thestop lug 290 by means of a shaft 296. In the projecting position shownin FIGS. 16 and 17 the stop lug is intended to co-operate with a lowerpart of the slide 205 of the drill rod centralizer thereby locking theslide against forward displacement.

In FIG. 12, a top view is shown of the devices 21 for exchanging thedrill bit arranged symmetrically at either side of the feed bar 14. Anarm 251 is attached to the feed bar 14. The other end of said arm isconnected to a plate 252. The plate 252 extends between two plates, anupper plate 253 and a lower plate 254, located in planes normal to thelongitudinal direction of the feed bar. A bearing bushing 255 for acurved arm 256 is attached to the one end face of the plate 252. The oneend of the arm 256 carries a device 21 for exchanging the drill bit andthe other end is pivotally connected to a piston rod 257 of a hydrauliccylinder 258. If the piston rod 257 is projected the center of thedevice 21 will move along the circle arc L₂ to the drill axis.

As may be seen in FIG. 13 the device 21 for exchanging a drill bitcomprises an outer casing 259 and a basket 260 mounted therein. Threesprings 261 arranged symmetrically around the basket extend between thebottom 262 of the casing and a thickened part 264 of the basket. Thespring 261 is pushed on a rod 263 screwed into the thickened part 264.On the outside of the basket 260 there are flanges 265 and 266. Aguiding rule 267 attached to the inside of the casing 259 extendsbetween these flanges. The guiding rule 267 and the flanges 265 and 266prevent the basket 260 from being turned relative to the casing 259. Inthe bottom of the basket 260 there are shoulders 268 intended forco-operation with a drill bit brought into the basket to prevent thedrill bit from being turned relative to the basket. In the bottom of thebasket and the casing respectively there are draining holes respectively269 and 270. At the upper part of the basket 260 there is a flange 271which extends along about half the circumference of the basket.

The arrangement according to the invention operates as follows. The rockdrilling machine 15 is moved along the feed bar 14 to a position behindthe drill rods 25 in the magazine. The transferring arm 26 is swung bythe motor 59 towards the magazine at the same time as the rollers 74, 75and 76, 77 respectively are moved away from each other by the cylindersrespectively 78 and 79. The transferring arm stops when the rollers 84and 85 come into contact with a rod 25. The rollers 74-77 are movedagainst the rod, which thereby is held by the gripping tongs formed bythe above rollers. The transferring arm takes the rod in abovementionedmanner to the drill axis. A device 21 for changing drill bits with adrill bit placed therein is swung to the drill axis. By rotating theinclined rollers 84 and 85 the rod 25 is screwed into the drill bitwhich is non-rotatably held by the bit exchanging device. During theseoperations the drill rod centralizer 20 is in a position above the bitexchanging devices and is locked in this position by means of thehydraulically operated lugs 290, which are movable in a directionperpendicular to the longitudinal direction of the feed bar 14 and whichare intended for co-operation with the slide 205. When the drill bit hasbeen screwed on, the rock drilling machine 15 is fed towards the rod 25and its adapter is screwed into a coupling sleeve which in turn isalready screwed on the rear end of the rod. The gripping tongs areopened and the transferring arm 26 is swung towards the magazine andstays there while gripping the rod coming next by the gripping tongs.

The rod 25 is drawn up by means of the rock drilling machine until thedrill bit reaches the bit guide of the tube 201. The bit exchangingdevice 21 is now swung away from the drill axis. The jaws 209 and 210 inthe drill rod centralizer 20 are brought together and the lugs 290 aremoved out of engagement with the slide 205. The drill rod centralizer isnow carried by the drill bit by the resting of the latter against thelower end face of the sleeve 224. The rock drilling machine is fed aheaduntil the drill rod centralizer with its flange 225 rests against theground. By the fact that the whole drill rod centralizer with the bitguiding tube slides down to abutment against the ground, there isachieved an effective guiding of the bit during the collaring, by meansof which the hole really gets the direction to which the feed bar hasbeen adjusted. This fact makes possible that the collaring can becarried out with full efficiency independently of the nature of theground. During collaring where the rock surface is covered by a looseoverburden, a crater arises easily around the hole. In this case the bitguiding tube follows to the bottom of the crater and there guides thedrill bit. If a great accuracy regarding direction and straightness ofthe hole is required the drill bit can be designed with an extendedguiding length. The tube 223 of the drill rod centralizer is connectedto a drill dust suction system (not shown). By the good ground contactand by the good accordance with the hole diameter of the drill bitguiding tube there is also achieved an effective removal of drill dust.During drilling, the jaws 209 and 210 will on the one hand guide thedrill rod and on the other seal against a rearward blowing-out of thedrill dust. The ring 222 contributes to a still improved sealing for theblowing-out of drill dust.

When the drill rod has been drilled down so far that the coupling sleeve221 screwed on the rear end thereof has reached the sleeve 218, thedrilling is broken off. The rock drilling machine is rotated in areverse direction, and the adapter is screwed out of the couplingsleeve. A sleeve brake 151 placed on the slide of the rock drillingmachine is swung automatically towards and against the sleeve 221 duringthe reverse rotation of the rock drilling machine. During the unscrewingof the adapter, the sleeve, then, will remain on the end of the drillrod. After the unscrewing of the adapter, the rock drilling machine ismoved backwards along the feed bar to a position above the magazinemember 24. After that the transferring arm 26 takes a new drill rod tothe drill axis. When in alignment with the drill axis, the drill rod isscrewed into the coupling sleeve on the rod next ahead by rotating themotors 82 and 83 of the gripping tongs. The string, being in the drillhole, is guided during the coupling by the jaws 209, 210. The adapter ofthe rock drilling machine is screwed into the coupling sleeve of the newdrill rod and the transferring arm 26 is swung to the magazine where thetongs grip the rod coming next. The time during which the sleeve passesthe jaws 209, 210 while being moved downwards, the jaws have to beopened. Sealing and guiding are then instead secured against the outerdiameter of the sleeve by the fact that the fixed passages 224 and 218respectively which are mounted respectively below and above the jawshave an inner diameter which is about equal to the outer diameter of thesleeve. The drilling continues until the desired hole depth is reachedor until the drill bit because of wear has to be exchanged for a newone.

Before the drill string is drawn up out of the hole the threadsincorporated in the string are shaken to come loose by the impactor ofthe rock drilling machine while the bit rests against the bottom of thehole. The drill rod centralizer 20 is drawn up along the feed bar by theresting of the coupling sleeve 221 against the underside of the jaws209, 210 during the withdrawal of the string. The drill rod centralizeris kept in a drawn-up position by means of the hydraulically operatedlugs 290. During the withdrawal, the jaws 209, 210 serve to grasp aroundand under the coupling sleeves 221 in order to hold the string in thehole. The transferring arm 26 is swung to the drill axis, where thetongs grip the rod, after which the adapter of the rock drilling machineis screwed out of the coupling sleeve of the uppermost drill rod,whereas the sleeve brake 151 safeguards that the sleeve remains on therod. The rod is after that screwed out of the sleeve being in the drillrod centralizer 20 by means of the spinning device 27 and is transferredto the magazine. The axially affixed position of the drill rodcentralizer has been arranged with respect to the bottom of the magazineso that the rod being unscrewed is at the right height. The rockdrilling machine, then, is moved down and draws up the string anotherrod length, after which the next rod is unscrewed and is transferred tothe magazine. The withdrawal of drill rods continues in the same wayuntil only the last rod is left. This rod is drawn up by the rockdrilling machine until the drill bit reaches the bit guiding tube 201.If the drill bit has to be exchanged, an empty bit exchanging device 21is swung into the drill axis. The drill bit is brought down into thebasket 260 of the bit exchanging device. The basket moves toward thebottom of the casing 259 while compressing the springs 261. The movementof the basket 260 continues until its flange 271 is brought to restagainst the annular flange 225 of the drill rod centralizer. In certaincases, the drill bit is stuck so firmly that its thread has to be blownto come loose by means of the impactor of the rock drilling machine. Inso doing, the basket 260 will form an anvil for the drill bit. Thestresses on the bit exchanging device generated by the blows istransmitted to the drill rod centralizer via the flange 271 and is takenup by the lugs 290. Therefore, there is no risk of breaking thesuspension of the casing 259. The adapter of the rock drilling machineis screwed out of the coupling sleeve, after which the spinning device27 unscrews the drill rod from the drill bit. The bit exchanging devicewith the worn bit is swung aside and the other bit exchanging devicewith a sharpened bit is swung to the drill axis. The sharpened bit isscrewed on the rod after which the string is assembled and a continueddrilling is carried out.

If a joint in the string has not gotten loose, this one has to be brokenmanually. This system is economically the most advantageous providedthat it is not frequently that manual breaking has to be resorted to. Ifnecessary, however, the slide of the drill rod centralizer can becompleted on the one hand with a couple of non-rotating jaws with agreater clamping capacity than the ones shown and gripping about theround drill rod below the coupling sleeve and on the other with aswingable and turnable pipe wrench, which grips about the round rodabove the sleeve.

What we claim is:
 1. An arrangement in drill rigs for moving drillstring elements to and fro between a drill string element magazine and adrill string and for connecting and disconnecting, respectively, saiddrill string elements to and from said drill string comprising: anelongated support (14), a drilling machine (15) movably mounted on saidsupport for reciprocal movement therealong, a plurality of drill stringelements (25) for making up a drill string, a magazine (22, 23, 24) forstoring said drill string elements, a device (26) for transferring adrill string element between said magazine and said drill string, means(27) on said transferring device for spinning a drill string elementgripped thereby, said spinning means including gripping means forgripping said drill string element during transferring thereof and foraxially displacing said drill string element during the spinning thereofso as to provide axial displacement of said drill string element duringthe connecting and disconnecting thereof.
 2. In an arrangement in drillrigs for moving drill string elements provided with coupling threads toand fro between a drill string element magazine (22, 23, 24) and a drillstring, an elongated support (14), an arm (56) swingably mounted at saidsupport, power means (59) for swinging said arm, a spinning device (74,75, 84) mounted at the free end of said arm for gripping and rotating adrill string element gripped thereby, said spinning device comprisingmutually opposed rollers (74, 75, 84) adapted to rest against the drillstring element at the gripping thereof, the axis of at least one of saidrollers being inclined relative to the drill string to impart an axialdisplacement of a gripped drill string element during spinning thereofduring connecting and disconnecting thereof.
 3. An arrangement accordingto claim 2 comprising power means for rotating said spinning deviceabout an axis substantially parallel to the axis of the drill string. 4.An arrangement according to claim 2 in which said spinning devicecomprises three rollers (74, 75, 84), one (84) of which is reversiblydriven, the other rollers (74, 75) being swingably mounted for selectivemovement to and from a drill string element, and power means forswinging said other rollers to and from a drill string element when thedrill string element is resting against said driven roller.
 5. Anarrangement according to claim 2 wherein said drill string element andsaid rollers contact each other along a contact surface which movesalong a helical path on the periphery of said drill string elementduring the rotation thereof.
 6. An arrangement according to claim 5wherein the coupling threads of the drill string elements have givenpitch angles, and wherein the axis of each of said rollers is inclinedrelative to the drill string, the angle between the axes of each of saidrollers, respectively, and the axis of the drill string beingsubstantially equal to the pitch angle of the thread of a drill stringelement.
 7. In an arrangement in drill rigs for moving drill stringelements provided with coupling threads of given pitch angles to and frobetween a drill string element magazine and a drill string axis, anelongated support (14), a drilling machine (15) movably mounted on saidsupport for reciprocal movement therealong, a magazine (22, 23, 24)fixedly mounted on said support for carrying a plurality of drill stringelements (25) stacked therein in substantially parallel relation to saidsupport, a first arm (56), means for swingably mounting said first armto said support, said mounting means including power means (59) forswinging said first arm, a second arm (57) swingably mounted to saidsupport, means (58) for interconnecting said first and second arms, arectangular frame (66, 67, 68, 69) having at least a pair of free endsand disposed between said first and second arms, means including powermeans (72) for rotatably journalling said rectangular frame at the freeends thereof to said first and second arms, a spinning device forrotating a drill string element, said spinning device comprising aduality of gripping means (74, 75, 84; 76, 77, 83) disposed at opposedsides of said rectangular frame, each of said gripping means comprisingthree rollers, the axes of said rollers being inclined relative to thedrill string axis, the angle between the axes of each of the rollersrespectively and the drill string axis being equal to the pitch angle ofthe thread of a drill string element, one (84; 85) of said three rollersbeing reversibly driven, the other rollers being swingably mounted forselective movement to and from a drill string element when the drillstring element is resting against said driven roller.
 8. An arrangementaccording to claim 7 in which said magazine is arcuate, the drill stringelements (25) are movable along an arc (L) with substantially the sameradius as the arc of said magazine during the swinging of said first andsecond arms, control means (107-113) for controlling the swinging androtating respectively of respectively said arms and said rectangularframe such that a drill string element is moved along an omegoid-shapedpath during the transferring between said magazine and the drill stringaxis.
 9. An arrangement according to claim 8 in which said control meanscomprise a third arm (107) limitedly swingably mounted on said secondarm, a sensor device (113) mounted on at least one of said support andthe one end of said third arm, means (112) on at least one of the oneend of said third arm and said support and adapted to cover said sensordevice after a given swinging of said second arm, said sensor devicedelivering a signal at the covering thereof, means responsive to saidsignal for stopping the swinging of said second arm and for starting therotation of said frame, a first (110) and a second pin (111) fixedlymounted relative to said frame adapted to co-operate alternately withthe other end of said third arm at the rotating of said frame foruncovering said sensor device, said sensor device delivering a furthersignal at the uncovering thereof, and means responsive to said furthersignal for starting a continued swinging of said second arm.
 10. Anarrangement according to claim 8 in which said magazine comprises atleast two axially spaced magazine rack members (23, 24), a plurality ofturnstiles (29) in each of said magazine members for separating twoadjacent drill string elements (25), said turnstiles being rotatablyjournalled in said magazine members, said turnstiles being disposedalternately on the one side and the other respectively of an arcuatechannel (28) from the opening to the bottom of said channel.
 11. Anarrangement according to claim 10 wherein said magazine comprises aplurality of shafts (41) rotatably journalled in said magazine rackmembers, one shaft for each of said turnstiles, wedge means (40)coupling each of said turnstiles to said shafts, a waved cam profile(51) provided with tops and bottoms in said magazine members for each ofsaid turnstiles, said wedge means of each turnstile being adapted toslide along said cam profile at the rotating of said turnstiles forproviding a locking thereof when said wedge means is disposed in abottom of said waved cam profile.
 12. Drill rod handling apparatus, foruse with earth drilling machines, comprising: a magazine for storingdrill rods, means for transferring a drill rod between said magazine andthe drill axis, and means for connecting and disconnecting,respectively, said drill rod to and from a drill string by spinning saiddrill rod, said connecting and disconnecting means including means forgripping a drill rod during transferring thereof and for axiallydisplacing a gripped rod by the spinning of said drill rod.
 13. In anarrangement in drill rigs for connecting and disconnecting drill stringelements movable to and fro between a drill string element magazine anda drill string axis, an elongated support (14), a drilling machine (15)movably mounted on said support for reciprocal movement therealong, aplurality of drill string elements (25) for making up a drill string, adrill string element storing magazine (22, 23, 24), means (26) formoving said drill string elements between said magazine and said axis, adrill string centralizing means (20) at the front end of said supportfor guiding the part of the drill string extending forwardly of saidsupport, at least one jaw (209) in said centralizing means movablymounted towards and away from said drill string, said drill string beingwidened at the connections (221) between two consecutive drill stringelements, and means for moving said centralizing means (20) axiallyalong said support by said drill string during axial movement of saiddrill string, said moving means including means for bringing said atleast one jaw towards and under said widened parts of the drill string.14. An arrangement according to claim 13 in which the front part (201)of said drill string element centralizing means at the extreme forwardposition on said support extends forwardly of the support, said frontpart being tubular with substantially the same inner diameter as theouter diameter of a drill bit (19) carried by said drill string, saidcentralizing means including a further part (218) situated immediatelybefore said at least one jaw, said further part being tubular withsubstantially the same inner diameter as the outer diameter of saidwidened parts of the drill string, and means (223) for removal ofdrilling dust connected between said tubular parts.
 15. An arrangementin drill rigs for connecting and disconnecting drill string elementsmovable to and fro between a drill string element magazine and a drillstring axis comprising an elongated support (14), a drilling machine(15) movably mounted on said support for reciprocal movement therealong,a drill string element storing magazine (22, 23, 24), a plurality ofdrill string elements (25) for making up a drill string, an adapter insaid drilling machine for the connection thereof to said drill string.[.and for removing a drill string element from said drill string.]. adevice (26) for moving said drill string elements between said magazineand said drill string axis, detachable coupling sleeves (221) forinterconnecting two consecutive drill string elements, a brake (151)mounted on said drilling machine for non-rotatably holding said couplingsleeves, said brake being movable between an inactive position where itis out of engagement with said coupling sleeves of the drill string andan active position where it cooperates with said coupling sleeves of thedrill string .[.for rotation between the held coupling sleeves and theuppermost drill string element.]., thereby insuring that the couplingsleeve on the drill string element nearest to said drilling machineremains on that drill string element when said adapter is disconnectedtherefrom.
 16. An arrangement according to claim 15 in which said brakecomprises an arm (161) pivotally attached to said drilling machine, twolegs (152, 153) swingably mounted on the outer end of said arm andadapted to rest against opposed sides of a coupling sleeve when thebrake is in its active position, a shaft (158) extending between andpast said legs, stop means (159, 160) on the outer ends of said shaft,and springs (156, 157) mounted on said shaft between said stop means andsaid legs for biasing said legs towards each other.
 17. In anarrangement in drill rigs for moving drill string elements provided withcoupling threads of given pitch angles to and fro between a drill stringelement magazine (22, 23, 24) and a drill string, an elongated support(14), an arm (56) swingably mounted to said support, power means (59)for swinging said arm relative to said support, a spinning device (74,75, 84) mounted at the free end of said arm for gripping and rotating adrill string element gripped thereby, said spinning device comprisingmutually opposed rollers (74, 75, 84) adapted to rest against the drillstring element at the gripping thereof, said rollers being mounted withtheir axes inclined at given angles to the axis of the drill string,said angles being substantially the same as the pitch angle of thecoupling thread of a drill string element.
 18. An arrangement accordingto claim 17 in which said spinning device comprises three rollers (74,75, 84), one (84) of which is reversibly driven, the other rollers (74,75) being swingably mounted for relative movement to and from a drillstring element, and power means for swinging said other rollers to andfrom a drill string element when the drill string element is restingagainst said driven roller.
 19. An arrangement according to claim 17,comprising power means (72) for rotating said spinning device about anaxis substantially parallel to the axis of the drill string.
 20. Anarrangement according to claim 19 in which said magazine is arcuate, thedrill string elements (25) are movable along an arc (L) withsubstantially the same radius as the arc of said magazine during theswinging of said arm, control means (107-113) for controlling theswinging and rotating respectively of respectively said arm and saidspinning device such that a drill string element is moved along anomegoid-shaped path during the transferring between said magazine andthe drill string axis. .Iadd.
 21. An arrangement in drill rigs forconnecting and disconnecting drill string elements movable to an frobetween a drill string element magazine and a drill string axis,comprising an elongate support, a drilling machine (15) mounted to saidsupport for reciprocal movement along said support, a plurality of drillstring elements (25) for making up a drill string, an adapter in saiddrilling machine for the connection thereof to said drill string forrotating said drill string, detachable coupling sleeves (221) forinterconnecting both said adapter and a first drill string elementnearest to said drilling machine and two consecutive drill stringelements, a brake (151) mounted on said drilling machine for movement incommon with said drilling machine along said support, said brakenon-rotatably holding a first coupling sleeve interconnecting saidadapter and said first drill string element during a disassembly of saiddrill string, said brake (151) being movable between an inactiveposition where it is out of engagement with said first coupling sleeveand an active position where it cooperates with said first couplingsleeve, thereby insuring that said first coupling sleeve on said firstdrill string element remains on said first drill string element whensaid adapter is disconnected therefrom. .Iaddend. .Iadd.22. Anarrangement according to claim 21 in which said brake comprises an arm(161) pivotally attached to said drilling machine, two legs (152, 153)swingably mounted on the outer end of said arm and adapted to restagainst opposed sides of a coupling sleeve when the brake is in itsactive position, and biasing means (156, 157) for biasing said legstoward each other in order to non-rotatably hold said coupling sleeve..Iaddend.